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ISSN: 2056-9890

Bis(4-meth­­oxy-3,4-di­hydro­quinazolin-1-ium) chloranilate

aDepartment of Chemistry, Faculty of Science, Okayama University, Okayama 700-8530, Japan
*Correspondence e-mail: ishidah@cc.okayama-u.ac.jp

(Received 20 August 2013; accepted 22 August 2013; online 31 August 2013)

In the title compound [systematic name: bis­(4-meth­oxy-3,4-di­hydro­quinazolin-1-ium) 2,5-di­chloro-3,6-dioxo­cyclo­hexa-1,4-diene-1,4-diolate], 2C9H11N2O+·C6Cl2O42−, the chloranil­ate anion lies about an inversion center. The 4-meth­oxy-3,4-di­hydro­quinazolin-1-ium cations are linked on both sides of the anion via bifurcated N—H⋯(O,O) and weak C—H⋯O hydrogen bonds, giving a centrosymmetric 2:1 aggregate. The 2:1 aggregates are linked by another N—H⋯O hydrogen bond into a tape running along [1-10]. The tapes are further linked by a C—H⋯O hydrogen bond into a layer parallel to the ab plane.

Related literature

For NMR and nuclear quadrupole resonance (NQR) studies on proton-transfer in the short hydrogen-bond of the diazine–chloranilic acid (2:1) system, see: Nihei et al. (2000[Nihei, T., Ishimaru, S., Ishida, H., Ishihara, H. & Ikeda, R. (2000). Chem. Phys. Lett. 329, 7-14.]); Seliger et al. (2009[Seliger, J., Žagar, V., Gotoh, K., Ishida, H., Konnai, A., Amino, D. & Asaji, T. (2009). Phys. Chem. Chem. Phys. 11, 2281-2286.]). For a related structure, see: Gotoh & Ishida (2011[Gotoh, K. & Ishida, H. (2011). Acta Cryst. C67, o500-o504.]). For the double π system of the chloranilate anion, see: Andersen (1967[Andersen, E. K. (1967). Acta Cryst. 22, 196-201.]); Benchekroun & Savariault (1995[Benchekroun, R. & Savariault, J.-M. (1995). Acta Cryst. C51, 186-188.]).

[Scheme 1]

Experimental

Crystal data
  • 2C9H11N2O+·C6Cl2O42−

  • Mr = 533.37

  • Triclinic, [P \overline 1]

  • a = 4.9971 (4) Å

  • b = 8.6363 (4) Å

  • c = 13.5808 (9) Å

  • α = 97.869 (4)°

  • β = 91.660 (6)°

  • γ = 100.968 (5)°

  • V = 569.06 (7) Å3

  • Z = 1

  • Mo Kα radiation

  • μ = 0.34 mm−1

  • T = 200 K

  • 0.45 × 0.35 × 0.04 mm

Data collection
  • Rigaku R-AXIS RAPID II diffractometer

  • Absorption correction: numerical (NUMABS; Higashi, 1999[Higashi, T. (1999). NUMABS. Rigaku Corporation, Tokyo, Japan.]) Tmin = 0.887, Tmax = 0.987

  • 7422 measured reflections

  • 2692 independent reflections

  • 1913 reflections with I > 2σ(I)

  • Rint = 0.199

Refinement
  • R[F2 > 2σ(F2)] = 0.082

  • wR(F2) = 0.177

  • S = 0.84

  • 2692 reflections

  • 172 parameters

  • H atoms treated by a mixture of independent and constrained refinement

  • Δρmax = 0.89 e Å−3

  • Δρmin = −0.54 e Å−3

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A D—H H⋯A DA D—H⋯A
N1—H1⋯O1 0.95 (3) 1.79 (3) 2.706 (2) 160 (3)
N1—H1⋯O2i 0.95 (3) 2.56 (3) 3.229 (3) 127 (2)
N2—H2⋯O2ii 0.90 (3) 1.87 (3) 2.762 (3) 171 (3)
C4—H4⋯O1iii 0.95 2.34 3.214 (3) 152
C10—H10⋯O1 0.95 2.52 3.230 (3) 131
Symmetry codes: (i) -x+1, -y, -z+1; (ii) x-1, y+1, z; (iii) -x+1, -y+1, -z+1.

Data collection: PROCESS-AUTO (Rigaku/MSC, 2004[Rigaku/MSC. (2004). PROCESS-AUTO and CrystalStructure. Rigaku/MSC Inc., The Woodlands, Texas, USA.]); cell refinement: PROCESS-AUTO; data reduction: CrystalStructure (Rigaku/MSC, 2004[Rigaku/MSC. (2004). PROCESS-AUTO and CrystalStructure. Rigaku/MSC Inc., The Woodlands, Texas, USA.]); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); molecular graphics: ORTEP-3 for Windows (Farrugia, 2012[Farrugia, L. J. (2012). J. Appl. Cryst. 45, 849-854.]); software used to prepare material for publication: CrystalStructure and PLATON (Spek, 2009[Spek, A. L. (2009). Acta Cryst. D65, 148-155.]).

Supporting information


Comment top

The title compound was accidentally obtained in the preparation process of bis(quinazolinium) chloranilate, which is an interesting candidate for the study on proton-transfer in short hydrogen-bonded systems (Nihei et al., 2000, Seliger et al., 2009) and also for the study on D—H···A hydrogen bonding (D = N, O, or C; A = N, O or Cl) in amine–chloranilic acid systems (Gotoh & Ishida, 2011).

In the crystal structure of the title compound, an acid-base interaction involving proton transfer is observed between chloranilic acid and 4-methoxy-3,4-dihydroquinazoline. The chloranilate ion shows a characteristic structure having four short C—C bonds and two extremely long C—C bonds, and C—O with similar bond lengths, which is explainable in terms of the double π system of the anion (Andersen, 1967; Benchekroun & Savariault, 1995). One chloranilate anion and two 4-methoxy-3,4-dihydroquinazolin-1-ium cations are linked by bifurcated N—H···(O,O) and weak C—H···O hydrogen bonds (N1—H1···O1, N1—H1···O2i and C10—H10···O1; symmetry code as in Table 1) to afford a centrosymmetric 2:1 aggregate (Fig. 1). The 2:1 aggregates are linked by another N—H···O hydrogen bond (N2—H2···O2ii; symmetry code as in Table 1), forming a tape along the [110] direction (Fig. 2). The tapes are further linked by a C—H···O hydrogen bond (C4—H4···O1iii; symmetry code as in Table 1) into a layer parallel to the ab plane.

Related literature top

For NMR and nuclear quadrupole resonance (NQR) studies on proton-transfer in the short hydrogen-bond of the diazine–chloranilic acid (2:1) system, see: Nihei et al. (2000); Seliger et al. (2009). For a related structure, see: Gotoh & Ishida (2011). For the double π system of the chloranilate anion, see: Andersen (1967); Benchekroun & Savariault (1995).

Experimental top

To a solution of chloranilic acid (183 mg) in acetonitrile (40 ml), a solution of quinazoline (228 mg) in acetonitrile (40 ml) was added at room temperature. A brown precipitate, which was immediately formed after mixing the solutions, was collected by filtration and then dissolved in methanol (40 ml). Single crystals of the title compound were obtained by slow evaporation from the methanol solution for ca three months at room temperature. During the slow evaporation process, quinazoline reacted with methanol under an acidic condition of chloranilic acid, yielding 4-methoxy-3,4-dihydroquinazoline.

Refinement top

C-bound H atoms were positioned geometrically (C—H = 0.95 or 0.98 Å) and refined as riding, allowing for free rotation of the methyl group. Uiso(H) values were set at 1.2Ueq(C) or 1.5Ueq(methyl C). The N-bound H atom was found in a difference Fourier map and refined isotropically. The refined N—H distances are 0.90 (3) and 0.95 (3) Å. The quality of the crystals studied were low as indicated by Rint = 0.199. This is possibly due to a small amount of quinazoline which remained without reacting with methanol and incorporated in the crystallization of the title compound as an impurity.

Computing details top

Data collection: PROCESS-AUTO (Rigaku/MSC, 2004); cell refinement: PROCESS-AUTO (Rigaku/MSC, 2004); data reduction: CrystalStructure (Rigaku/MSC, 2004); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: ORTEP-3 for Windows (Farrugia, 2012); software used to prepare material for publication: CrystalStructure (Rigaku/MSC, 2004) and PLATON (Spek, 2009).

Figures top
[Figure 1] Fig. 1. The molecular structure of the title compound, with the atom-labeling. Displacement ellipsoids of non-H atoms are drawn at the 50% probability level. The dashed lines indicate N—H···O and C—H···O hydrogen bonds. [Symmetry code: (i) -x + 1, -y, -z + 1.]
[Figure 2] Fig. 2. A partial packing diagram of the title compound. The dashed lines indicate N—H···O and C—H···O hydrogen bonds. H atoms of the not involved in the hydrogen bonds have been omitted. [Symmetry codes: (i) -x + 1, -y, -z + 1; (ii) x - 1, y + 1, z.]
Bis(4-methoxy-3,4-dihydroquinazolin-1-ium) 2,5-dichloro-3,6-dioxocyclohexa-1,4-diene-1,4-diolate top
Crystal data top
2C9H11N2O+·C6Cl2O42Z = 1
Mr = 533.37F(000) = 276.00
Triclinic, P1Dx = 1.556 Mg m3
Hall symbol: -P 1Mo Kα radiation, λ = 0.71075 Å
a = 4.9971 (4) ÅCell parameters from 6359 reflections
b = 8.6363 (4) Åθ = 3.0–28.0°
c = 13.5808 (9) ŵ = 0.34 mm1
α = 97.869 (4)°T = 200 K
β = 91.660 (6)°Platelet, brown
γ = 100.968 (5)°0.45 × 0.35 × 0.04 mm
V = 569.06 (7) Å3
Data collection top
Rigaku R-AXIS RAPID II
diffractometer
1913 reflections with I > 2σ(I)
Detector resolution: 10.00 pixels mm-1Rint = 0.199
ω scansθmax = 27.9°
Absorption correction: numerical
(NUMABS; Higashi, 1999)
h = 66
Tmin = 0.887, Tmax = 0.987k = 1111
7422 measured reflectionsl = 1717
2692 independent reflections
Refinement top
Refinement on F2Primary atom site location: structure-invariant direct methods
Least-squares matrix: fullSecondary atom site location: difference Fourier map
R[F2 > 2σ(F2)] = 0.082Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.177H atoms treated by a mixture of independent and constrained refinement
S = 0.84 w = 1/[σ2(Fo2) + (0.P)2]
where P = (Fo2 + 2Fc2)/3
2692 reflections(Δ/σ)max < 0.001
172 parametersΔρmax = 0.89 e Å3
0 restraintsΔρmin = 0.54 e Å3
Crystal data top
2C9H11N2O+·C6Cl2O42γ = 100.968 (5)°
Mr = 533.37V = 569.06 (7) Å3
Triclinic, P1Z = 1
a = 4.9971 (4) ÅMo Kα radiation
b = 8.6363 (4) ŵ = 0.34 mm1
c = 13.5808 (9) ÅT = 200 K
α = 97.869 (4)°0.45 × 0.35 × 0.04 mm
β = 91.660 (6)°
Data collection top
Rigaku R-AXIS RAPID II
diffractometer
2692 independent reflections
Absorption correction: numerical
(NUMABS; Higashi, 1999)
1913 reflections with I > 2σ(I)
Tmin = 0.887, Tmax = 0.987Rint = 0.199
7422 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0820 restraints
wR(F2) = 0.177H atoms treated by a mixture of independent and constrained refinement
S = 0.84Δρmax = 0.89 e Å3
2692 reflectionsΔρmin = 0.54 e Å3
172 parameters
Special details top

Geometry. All e.s.d.'s (except the e.s.d. in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell e.s.d.'s are taken into account individually in the estimation of e.s.d.'s in distances, angles and torsion angles; correlations between e.s.d.'s in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell e.s.d.'s is used for estimating e.s.d.'s involving l.s. planes.

Refinement. Refinement of F2 against ALL reflections. The weighted R-factor wR and goodness of fit S are based on F2, conventional R-factors R are based on F, with F set to zero for negative F2. The threshold expression of F2 > σ(F2) is used only for calculating R-factors(gt) etc. and is not relevant to the choice of reflections for refinement. R-factors based on F2 are statistically about twice as large as those based on F, and R- factors based on ALL data will be even larger.

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å2) top
xyzUiso*/Ueq
Cl10.92850 (10)0.01581 (6)0.33371 (4)0.0289 (2)
O10.6877 (3)0.26227 (17)0.41520 (12)0.0253 (4)
O20.6806 (3)0.27488 (17)0.44963 (13)0.0273 (4)
O30.0538 (3)0.67492 (19)0.17432 (13)0.0325 (4)
N10.3013 (4)0.3978 (2)0.33662 (15)0.0238 (4)
N20.0001 (4)0.5674 (2)0.32482 (16)0.0264 (4)
C10.6067 (4)0.1368 (2)0.45169 (16)0.0202 (5)
C20.6949 (4)0.0070 (2)0.42490 (16)0.0216 (5)
C30.6061 (4)0.1443 (2)0.46922 (16)0.0208 (5)
C40.1661 (4)0.5056 (2)0.37648 (17)0.0239 (5)
H40.19070.53990.44620.029*
C50.0403 (4)0.5353 (3)0.21674 (18)0.0276 (5)
H50.24130.50320.20030.033*
C60.0872 (4)0.3967 (3)0.17605 (18)0.0252 (5)
C70.0414 (5)0.3326 (3)0.07619 (19)0.0329 (5)
H70.07870.37230.03500.039*
C80.1683 (6)0.2118 (3)0.0362 (2)0.0375 (6)
H80.13650.16890.03230.045*
C90.3429 (5)0.1532 (3)0.0965 (2)0.0367 (6)
H90.43150.07070.06880.044*
C100.3890 (5)0.2130 (3)0.19591 (19)0.0305 (5)
H100.50750.17210.23700.037*
C110.2585 (4)0.3353 (3)0.23554 (17)0.0234 (5)
C120.3396 (6)0.7357 (3)0.1882 (2)0.0405 (6)
H12A0.38210.84060.16610.061*
H12B0.43770.66260.14930.061*
H12C0.39580.74590.25890.061*
H10.413 (6)0.351 (3)0.377 (2)0.037 (7)*
H20.097 (6)0.628 (4)0.362 (2)0.043 (8)*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
Cl10.0312 (3)0.0265 (4)0.0301 (4)0.0090 (2)0.0144 (2)0.0008 (3)
O10.0295 (8)0.0181 (7)0.0299 (9)0.0075 (6)0.0073 (6)0.0041 (7)
O20.0324 (8)0.0188 (8)0.0327 (9)0.0111 (6)0.0113 (7)0.0006 (7)
O30.0428 (10)0.0251 (8)0.0326 (10)0.0131 (7)0.0048 (7)0.0057 (8)
N10.0288 (9)0.0188 (9)0.0246 (10)0.0091 (7)0.0052 (7)0.0013 (8)
N20.0314 (10)0.0213 (9)0.0281 (11)0.0106 (8)0.0125 (8)0.0000 (9)
C10.0219 (9)0.0162 (10)0.0217 (11)0.0032 (8)0.0015 (8)0.0005 (9)
C20.0234 (10)0.0189 (10)0.0223 (11)0.0066 (8)0.0073 (8)0.0020 (9)
C30.0219 (9)0.0189 (10)0.0217 (11)0.0073 (8)0.0033 (8)0.0019 (9)
C40.0289 (10)0.0197 (10)0.0230 (12)0.0050 (8)0.0097 (8)0.0002 (10)
C50.0269 (10)0.0238 (11)0.0327 (13)0.0090 (9)0.0040 (9)0.0004 (10)
C60.0264 (10)0.0198 (10)0.0282 (12)0.0033 (8)0.0053 (8)0.0004 (10)
C70.0397 (13)0.0296 (12)0.0275 (13)0.0038 (10)0.0021 (10)0.0015 (11)
C80.0561 (16)0.0282 (13)0.0248 (13)0.0053 (11)0.0078 (11)0.0054 (11)
C90.0522 (15)0.0258 (12)0.0325 (14)0.0127 (11)0.0153 (12)0.0040 (12)
C100.0366 (12)0.0235 (11)0.0333 (14)0.0117 (10)0.0092 (10)0.0011 (11)
C110.0259 (10)0.0195 (10)0.0236 (12)0.0035 (8)0.0074 (8)0.0003 (9)
C120.0478 (15)0.0276 (13)0.0449 (16)0.0002 (11)0.0088 (12)0.0095 (12)
Geometric parameters (Å, º) top
Cl1—C21.730 (2)C5—C61.508 (3)
O1—C11.255 (3)C5—H51.0000
O2—C31.251 (2)C6—C111.384 (3)
O3—C51.413 (3)C6—C71.388 (4)
O3—C121.422 (3)C7—C81.379 (3)
N1—C41.319 (2)C7—H70.9500
N1—C111.399 (3)C8—C91.389 (4)
N1—H10.95 (3)C8—H80.9500
N2—C41.305 (3)C9—C101.374 (4)
N2—C51.457 (3)C9—H90.9500
N2—H20.90 (3)C10—C111.398 (3)
C1—C21.401 (3)C10—H100.9500
C1—C3i1.537 (3)C12—H12A0.9800
C2—C31.405 (3)C12—H12B0.9800
C3—C1i1.537 (3)C12—H12C0.9800
C4—H40.9500
C5—O3—C12115.09 (18)C11—C6—C7118.93 (19)
C4—N1—C11120.69 (19)C11—C6—C5121.3 (2)
C4—N1—H1120.9 (17)C7—C6—C5119.7 (2)
C11—N1—H1118.0 (17)C8—C7—C6120.7 (2)
C4—N2—C5124.17 (18)C8—C7—H7119.7
C4—N2—H2114.4 (19)C6—C7—H7119.7
C5—N2—H2121.4 (19)C7—C8—C9119.7 (2)
O1—C1—C2124.72 (19)C7—C8—H8120.2
O1—C1—C3i116.54 (16)C9—C8—H8120.2
C2—C1—C3i118.73 (18)C10—C9—C8120.8 (2)
C1—C2—C3123.38 (19)C10—C9—H9119.6
C1—C2—Cl1118.46 (16)C8—C9—H9119.6
C3—C2—Cl1118.15 (14)C9—C10—C11118.9 (2)
O2—C3—C2126.28 (19)C9—C10—H10120.6
O2—C3—C1i115.86 (18)C11—C10—H10120.6
C2—C3—C1i117.85 (16)C6—C11—C10121.0 (2)
N2—C4—N1123.2 (2)C6—C11—N1119.03 (18)
N2—C4—H4118.4C10—C11—N1120.0 (2)
N1—C4—H4118.4O3—C12—H12A109.5
O3—C5—N2110.61 (19)O3—C12—H12B109.5
O3—C5—C6113.51 (18)H12A—C12—H12B109.5
N2—C5—C6110.36 (18)O3—C12—H12C109.5
O3—C5—H5107.4H12A—C12—H12C109.5
N2—C5—H5107.4H12B—C12—H12C109.5
C6—C5—H5107.4
O1—C1—C2—C3178.1 (2)O3—C5—C6—C763.7 (3)
C3i—C1—C2—C32.3 (3)N2—C5—C6—C7171.5 (2)
O1—C1—C2—Cl11.1 (3)C11—C6—C7—C81.3 (4)
C3i—C1—C2—Cl1178.50 (14)C5—C6—C7—C8176.3 (2)
C1—C2—C3—O2178.8 (2)C6—C7—C8—C90.3 (4)
Cl1—C2—C3—O20.4 (3)C7—C8—C9—C100.6 (4)
C1—C2—C3—C1i2.3 (3)C8—C9—C10—C110.5 (4)
Cl1—C2—C3—C1i178.52 (14)C7—C6—C11—C101.4 (3)
C5—N2—C4—N15.1 (3)C5—C6—C11—C10176.1 (2)
C11—N1—C4—N24.4 (3)C7—C6—C11—N1178.9 (2)
C12—O3—C5—N264.7 (2)C5—C6—C11—N13.6 (3)
C12—O3—C5—C660.0 (3)C9—C10—C11—C60.5 (3)
C4—N2—C5—O3114.4 (2)C9—C10—C11—N1179.8 (2)
C4—N2—C5—C612.1 (3)C4—N1—C11—C64.8 (3)
O3—C5—C6—C11113.8 (2)C4—N1—C11—C10175.5 (2)
N2—C5—C6—C1111.0 (3)
Symmetry code: (i) x+1, y, z+1.
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
N1—H1···O10.95 (3)1.79 (3)2.706 (2)160 (3)
N1—H1···O2i0.95 (3)2.56 (3)3.229 (3)127 (2)
N2—H2···O2ii0.90 (3)1.87 (3)2.762 (3)171 (3)
C4—H4···O1iii0.952.343.214 (3)152
C10—H10···O10.952.523.230 (3)131
Symmetry codes: (i) x+1, y, z+1; (ii) x1, y+1, z; (iii) x+1, y+1, z+1.
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
N1—H1···O10.95 (3)1.79 (3)2.706 (2)160 (3)
N1—H1···O2i0.95 (3)2.56 (3)3.229 (3)127 (2)
N2—H2···O2ii0.90 (3)1.87 (3)2.762 (3)171 (3)
C4—H4···O1iii0.952.343.214 (3)152
C10—H10···O10.952.523.230 (3)131
Symmetry codes: (i) x+1, y, z+1; (ii) x1, y+1, z; (iii) x+1, y+1, z+1.
 

References

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